Proteomic profiling of the mouse heart surfaceome identified 834 enriched proteins in healthy hearts and 240 significantly altered proteins 24 hours post-ischaemia reperfusion injury.
Proteomic profiling of the mouse heart surfaceome identified 240 vascular-accessible proteins altered post-ischaemia reperfusion injury, revealing sex-specific targets for potential therapeutic nanocarrier delivery.
Abstract Background The surfaceome represents the cell membrane molecular landscape critical to inform the development of targeted therapies for the heart. Clinical use of nano-delivery systems to target injured myocardium following myocardial infarction (MI) and ischaemia reperfusion (I/R) injury is constrained by the lack of known vascular accessible protein targets for delivery. Proteomic profiling by mass spectrometry is key to identifying molecular targets that address post-MI injury and repair. Purpose To define the heart surfaceome and its remodelling in I/R. Insights into the altered molecular landscape is critical to inform the development of targeted therapies for the injured heart post-MI. Molecular targets guide therapeutic nanocarriers to increase efficacy of dosage and reduce loss of drug in off-target tissues, optimising therapeutic payload, costs and importantly patient safety. Method We developed a novel perfusion method to access the coronary arteries. We employed a membrane-impermeant, biotinylation strategy to selectively label extracellular and membrane-associated proteins in healthy and 24h I/R injured male and female mouse hearts. Avidin-based enrichment and mass-spectrometry based proteomics were used to identify cell surface proteins differentially expressed by sex and injury status. Results We successfully captured the surfaceome from male and female mice using a coronary perfusion strategy, providing novel insights into the vascular-accessible surface proteome. In healthy hearts, 834 extracellular and membrane-associated proteins were significantly enriched relative to total proteome, including cardiac extracellular and matricellular proteins such as LAMA isoforms, DCN, and BGN. Similarly, cell surface proteins including ATP1A1, DSC2, ITGA, SGCD, and ECSCR were localised to cytoskeletal–membrane junctions. Post-MI, 240 vascular-accessible proteins were significantly altered and commonly detected in male and female hearts. Among these, VTN (cell-matrix adhesion) and VAMP3 (vesicular trafficking) were associated with early remodelling. Female-specific proteins included PRG4 and CTSD, key mediators of ECM remodelling. In males, upregulated proteins such as CCN2 and ENPP2 reflected pro-fibrotic signalling, endothelial activation, and cytoskeletal remodelling following ischaemic injury. Conclusion We defined the vascular-accessible coronary network and mapped its remodelling following I/R injury, revealing distinct sex-specific molecular networks. These findings provide new insights into the post-ischaemic cardiac microenvironment and identify surface-accessible proteins as targets for therapeutic intervention.
Inocencio et al. (Fri,) conducted a other in Ischaemia reperfusion injury. Membrane-impermeant biotinylation and mass-spectrometry vs. Healthy hearts was evaluated on Differentially expressed cell surface proteins. Proteomic profiling of the mouse heart surfaceome identified 834 enriched proteins in healthy hearts and 240 significantly altered proteins 24 hours post-ischaemia reperfusion injury.